Table 2.

Future directions to improve AF classification

Potential questions	Examples of study measures that can be performed to address the questions
Are existing pattern-based AF classes valid and reliable?	Continuous telemetry monitoring Clinical and biological determinants of self-terminating AF Intraobserver and interobserver reliability comparisons
Are existing pattern-based AF classes or AF progression associated with differences in health outcomes that are independent of comorbid conditions?	Heart failure Dementia Quality of life Mortality Health-care expenditures
Do biological subtypes of disease manifest as different pattern-based classes of AF?	Patterns of genetic variation Phenotypic features
Can individuals at risk of new-onset, recurrent, or progressive AF be identified?	Genetic variants Biomarkers Electrocardiographic monitoring Imaging characteristics
Can new-onset, recurrent, or progressive AF be prevented?	Antiarrhythmics, dietary supplements Ablation
How does AF class change over time in each individual?	Longitudinal correlation of AF classification
Is there utility in preventing the progression of AF?	Health outcomes Cost-effectiveness assessment
What accounts for variability in AF patterns and progression?	Patterns of genetic variation Sex-specific patterns Racial-specific and ethnic-specific patterns Environmental exposures Comorbid conditions
Does classification of patient well-being inform prognosis and clinical management?	Quality of life Symptoms Novel well-being instruments
Can novel classification schemes explain variability in clinical outcomes better than existing pattern-based classification?	Predictors of AF outcomes Classification, discrimination, reclassification

Abbreviation: AF, atrial fibrillation